BIRJAND, Iran — Iran has achieved a landmark, with 3,000 centrifuges fully working in its controversial uranium enrichment program, President Mahmoud Ahmadinejad announced Wednesday.

"We have now reached 3,000 machines," Ahmadinejad told thousands of Iranians in Birjand in eastern Iran, in a show of defiance of international demands to halt the program believed to be masking the country's nuclear arms efforts.

Ahmadinejad has in the past claimed Iran succeeded in installing the 3,000 centrifuges at its uranium enrichment facility at Natanz.

Wednesday's claim was his first official statement that the plant is now fully operating the 3,000 centrifuges.

Centrifuges are used in enriching uranium, a process that can produce either fuel for a nuclear reactor or material for a warhead.